Ref. No. 37/1188
In the name of Allah the most Gracious the most Merciful
The answer to your question is as follows:
Offering two Rakat Nafl after witr is also proven in a Hadith. The prophet’s saying “Make the last of your prayer at night Witr” means one should pray witr after tahajjud. Hence, if a person prays Witr then he wants to offer a Nafl prayer etc. at night that is permissible too.
And Allah knows best
Darul Uloom Waqf Deoband